The John Bunn Oxygen Regulators by Graham Field are high-pressure medical devices designed to provide precise flow control for patients receiving oxygen therapy. These regulators maintain a consistent 50 psi outlet pressure and feature a click-style flow control knob for easy adjustment between 12 distinct settings. Each unit is equipped with a bumper-protected contents gauge that reads up to 3000 psi for clear visibility of tank levels. Available in both Yoke (CGA870) and Nut/Stem (CGA540) styles, they are built to be lightweight, durable, and compatible with various cylinder types.